Electrical condenser



April .15, 1930.

P. R. COURSEY ELECTRICAL CONDENSER Filed June 23, 1926 INVENTOR P/f/L/P e; Mum) z ATTORNEY Patented Apr. 15, 1930 PATENT OFFICE UNITED STATES PHILIP RAY COUBSEY, on RICHMOND, ENGLAND, ASSIGNOR T0 DURILIER CONDENSER CORPORATION, OF NEW YORK, N. Y., A CORPORATION OF DELAWARE ELECTRICAL CONDENSER Application med June 23; 1926, Serial No. 118,102, and. in Great Britain July 3; 1925.

This invention relates to electrical condensers, and particularly to electrical condensers mounted within a suitable housing of insulation.

An object of the invention is to provide a condenser which is required to operate at a considerable potential, and whichiis so constructed that it can be well encased and properly clamped so that the parts of the condenser can be maintained in the most efficient condition.

Other objects and advantages of the invention are set forth in the following description taken with the accompanying drawings, and the novel features are pointed out in the ap pended claims; but the description is illustrative only, and I may vary the details presented herein without departing from the principle of the invention or exceeding the broad meanings of the terms in which the appended claims are expressed.

On the drawings:

Figure 1 is a longitudinal section through a condenser of my invention.

Figure 2 is a top view thereof; and

Figure 3 is a cross section of the line 33 of Figure 1.

The same numerals identify the same parts throughout. i

The numeral 1 is utilized to indlcate the body of the condenser which comprises a sultable number of metallic plates or the like, separated by insulation andpncircled by a clamping ring 2. The condenser and ring are disposed in a suitable housing, which is shown as having the form of an open-ended tubular body orhousing 3, one end of wh ch is closed by a bottom 4 and the other by a top 5. At 6 and 7 are terminals for the condenser which may be in the form of bands, one of which is connected to the ring 2, and the other to the opposite terminal of the body of the condenser 1. This condenser may be designed as required, and it is shown as made up of a number of sections 8 separated by sheets of insulation 9. Inside of the ring 2 are clamping blocks 10 which engage the opposite ends of the condenser 1 and the ring may carry a screw 11 engaging one of the blocks so that when the screw is turned up, the condenser may be put under as much compression as is desired.

One of the terminal conductors 6 is connected to a binding post 12 in the top 5 and the other terminal conductor 7 is connected on which the body rests, and upon the. shoul-,

der the casing may have a projection bead or rib 18 opposite a corresponding groove 19 in the rim of the closure or top 5. The top fits loosely into the adjacent end of the body of the casing and is secured by cement 20, which hardens and forms a seal and so engages the rib 18 and the groove 19 asto hold the top in place.

The bottom 1 is provided with a circular rib 21, and the lower end of the body of the casing is encircled by this rib. This'rib projects inward somewhat, as indicated at 22 and the lower edge of the body of the casing is extended somewhat; as indicated at 23, so that while the lower end of the body is of less diameter than the diameter of the rib to enable the body to fit inside of the rib against the bottom 4. The insertion of cement 20 between the rib 21 and the body will act as in the case of the top 5 to secure the bottom of the casing and the body thereof tightly together making a sealed joint; the hardened cement 20 holding the extended end of the body against withdrawal past the inward proj ecting edge of the rib 21.

The binding posts 12 and 13 may consist of headed screws which are passed through the top 5 with the heads inside clamping the extremities of the conductors 6 and 7. When the closure or top 5 is put on the casing, the condenser 1 and the ring 2 suspended from this top, occupy the space inside'of the body.

parts inside of the casing are supported to the best advantage.

It is also apparent that the foregoing construction gives a uniform minimum spacing between the clamp 2 and body 3 at all adj acent points or faces which reduces the possibility of-breakdown of the condenser and also enables the over-all dimensions of the casing to be reduced.

Condensers of this construction are especially useful as anode stopping or anode feeding condensers to operate at a high voltage above the earth. They may also be employed as high-frequency by-pass condensers or as grid condensers in radio transmitters.

The top 5 is preferably made of some good insulation and the body of the casing 2 should be of some good insulation, such as porcelain. Preferably the bottom a is of metal.

For large transmitters requiring large anode-feed condensers, standard metal encased condensers may be used in place of the condenser 1, mounted upon porcelain insulators in the casing to provide the necessary insulation from earth. For very large radio transmitters the anode-feed condensers are supplied in the form of oil-filled steel tanks in which the complete condenser is supported on appropriate porcelain insulation.

The above described condenser is also suitable for use in low power transmit-ting circuits operating at 100 metres and below, for aerial series condensers, oscillation circuit condensers, grid condensers, etc.

The special object of this type of condenser is to meet the demand for anode feed condensersfgrid condensers, etc., for low power valve. transmitting purposes. For such use the condenser is called upon to carry small radio frequency currents not usually exceedmg one or two amperes super-imposed upon a. D. C. voltage of 3000 volts. From the position of the condenser in such circuits, the whole condenser is usually operated at a radio frequency potential to earth, and this construction with a porcelain case gives a very neat arrangement for this purpose, and avoids the use of any additional insulators for sup porting the condenser. This model is also finding favor for use in oscillation circuits of low power transmitters where it will have to carry only a few amperes of radio frequency current. It is quite useful also as an aerial series condenser for the same class of transmitters, as for those uses also the condenser can operate at a radio frequency potential to earth without additional insulators.

Having described my invention, what Ibelieve to be new and desire to secure and protect-by Letters Patent of the United States is 1. A condenser comprising a casing of insulati on, a bottom for said casing, the bottom having a flange, and the lower end of said casing being encircled by said flange, the

flange projecting towards the casing and the I lower end of the casing being extended to project towards the flange to enable the bottom and the body of the casing to be cemented together, the opposite end of the casing having a shoulder, a top for the casi-ngresting upon the shoulder, said top having a groove encircling the rim thereof, the casing having a projecting rib adjacent said groove, cement filling the space betweenthe rib and the rim of the top to secure the-top in place and seal the casing, a clamped eondenseirin the casing, binding posts mounted on the top and conductors attached to the binding posts and to the condenser and suspending the condenser in the casing.

2. A condenser comprising a casing of insulation, a bottom for said casing, the bottom having a flange, and the lower end of said casing being encircled by said flange, the flange projecting towards the casing and the lower end of the casing being extended to project towards the flange to enable the bottom and the body of the casing to be cemented together, the opposite end of the casing having a shoulder, a top for the casing resting upon the shoulder, said top having a groove encircling the rim thereof, the casing having a projecting rib adjacent said groove, cement filling the space between the rib and the rim of the top to secure the top in place and seal the casing, a condenser in the casing, binding posts mounted on the top and conductors attached to the binding posts and to the condenser.

In testimony whereof I afiix my signature.

PHILIP R. COURSEY. 

